A Fairfax County lawmaker has helped to create a new bi-partisan political caucus hoping to outlaw — or at least curb — the use of Automated License Plate Readers by Virginia law enforcement officials.

Sen. Chap Petersen (D-Fairfax) is a cofounder of the newly formed Ben Franklin Liberty Caucus, whose first order of business is to address the use of ALPRs in Virginia.

Petersen filed a bill in the Virginia legislature last term hoping to define the legal use of the technology, but later decided to table it until next session, so he could obtain more information about the controversial technology and its use by law enforcement officials. The caucus is one way in which he is doing that.

“My eventual goal is to limit, if not eliminate, its use in Virginia,” he said. “This caucus will help me toward achieving that goal.”

According to former Virginia Attorney General Ken Cuccinelli — who last year wrote a legal opinion about the use of ALPRs by Virginia law enforcement agencies — the devices use a combination of cameras and optical character recognition technology to read license plates and then transfer the information to a police car computer that then displays the vehicle registrant’s personal information.

The police computer runs that information through several databases, cross-matching it through the Department of Motor Vehicles and other agencies, instantaneously spitting out vast amounts of personal information about that person. That information is then kept for unregulated lengths of time within each jurisdiction’s own database, where it can be referenced again, and again.

“The more information they get, the more they can tell about who you are, what you do, what doctor you see, what psychologist you see, where your car is parked,” said Claire Guthrie Gastañaga, executive director of the Virginia chapter of the American Civil Liberties Union.

“Imagine, for example, that the police stored every one of the thousands of images captured per minute, accumulating a vast database that could show where a particular car was located on any particular day,” wrote Virginia ACLU Legal Director Rebecca Glenberg in a brief about ALPRs. “Or suppose an ALPR were mounted outside a controversial religious or political organization, so that police could monitor who regularly parks nearby.”

According to a 2009 Virginia State Police memo obtained by the Times, in 2008 state police used ALPRs for just that purpose at rallies for then-presidential candidate Barack Obama in Leesburg and Arlington, and one for then-vice presidential candidate Sarah Palin, also in Leesburg.

“[ALPRs] would detect any stolen vehicles attempting to enter the outer perimeter of the event and possibly allow for some record of attendees in the event a serious event occurred during the event,” wrote First Sergeant Alvin D. Blankenship in the memo, concerning the use of ALPRs at those rallies.

ALPRs were also used by Fairfax County Police in 2009 to scan nearly 70,000 license plates over five days in an effort to identify stolen cars, according to the same VSP memo.

The ACLU and other civil-liberties groups, such as the Rutherford Institute, based in Charlottesville, say that using the devices in such a way is clearly a breach of the 4th Amendment, which prohibits unreasonable searches without first obtaining a warrant.

Petersen agrees.

“It’s the classic ‘shoot first and ask questions later,’” he said. “In my opinion its use like that is an illegal search and therefore goes against the 4th amendment,” he said. “You can’t just gather information on innocent citizens, keep it, and then decide when it will become relevant to an investigation.”

In his legal opinion, former attorney general Cuccinelli outlines two uses of ALPRs.

In one, he says ALPRs used by law enforcement agencies searching for predetermined “criminal intelligence information” that has been “clearly established in advance” are legal.

In the other, he says any information gathered by police in an arbitrary “continuous passive manner … may not lawfully be collected through use of ALPR technology.”

Fairfax County Police spokesperson Lucy Caldwell declined to comment on exactly how the FCPD use ALPRs, saying only that “the FCPD does not comment on our investigative tools, nor do we discuss investigative techniques or capabilities … however, our detectives and officers follow all state and federal legal requirements for the use of technologies that we do use.”